This invention relates to an optical cable connecting section to be contained in an electric power and optical composite cable.
An example of a conventional submarine electric power and optical composite cable is shown in FIG. 5.
The composite cable in FIG. 5 has three electric power cables 11, an optical cable 12, an intermediate 13 made, for example, of jute, a retainer winding layer 14 made of a tape, a tension member 15 and an external sheath 16.
As apparent in FIG. 5, since the optical cable 12 is finer than the power cable 11, the optical cable 12 is ordinarily disposed in a slot between the adjacent power cables 11, so-called "shoulders" therebetween.
It is generally necessary to provide a connecting section of the power cable and a connecting section of the optical cable in the midway in such a submarine electric power and optical composite cable since the cable is lengthened. In this case, it is desired to form the outer diameters of the connecting sections substantially in the same diameter as those of the power cable or the optical cable so that the outer diameter of the entire cable does not vary in a longitudinal direction.
The power cables are heretofore connected in the same diameter.
However, the connecting sections of the optical cables must have excessive lengths by considering the correction when the connection of the optical fibers is mistaken, and the outer diameters of the connecting section of the optical cables become considerably larger than the outer diameters of the optical cables due to the accommodation of the excessive lengths therein.
As a result, the outer diameter of the cable of the portion which includes the connecting sections of the optical cables is locally increased to cause the laying work to become complicated, and an excessive external force might be additionally applied to the connecting sections of the optical cables.